JP2011236837A - Electric fan, and electric vacuum cleaner with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric fan having high reliability without damaging a step difference part even if an impeller is speedily rotated, and to provide an electric vacuum with the same.SOLUTION: The electric fan includes: a front shroud; a rear shroud; the impeller having a plurality of blades sandwiched by the front and rear shrouds; and a motor. A plurality of protrusions are provided where the front and rear shrouds of the blades contact. A fitting opening engaged with the protrusion is provided in the front and rear shrouds, and the fitting opening is formed so that an outer opening area of the fitting opening is made to be larger than an inner opening area of the fitting opening where the blades contact. The step difference part is provided so that the part is almost parallel to outer surfaces of the front and rear shrouds in the outer surface side of the fitting opening. A thickness of the step difference part is formed with the same one as the front and rear shrouds.

Description

  The present invention relates to an electric blower and a vacuum cleaner using the electric blower, and more particularly to an impeller of the electric blower.

  In the conventional electric blower, in order to improve the suction efficiency of the electric blower, the blade protrusion is fitted into the fitting hole of the fan plate, and the blade is fixed to the fan plate by crimping the protrusion. In the centrifugal fan of an electric blower, a centrifugal fan has been proposed in which a step portion substantially parallel to the outer surface of the fan plate is provided on the outer surface side of the fitting hole (see, for example, Patent Document 1).

  As such a conventional vacuum cleaner, for example, a vacuum cleaner having a configuration shown in FIGS.

  As shown in FIG. 4, the centrifugal fan of the electric blower includes a plurality of upper and lower fan plates 101 and 102 that are spaced apart from each other and a plurality of spaces that partition the space between the upper and lower fan plates 101 and 102. And a blade 106. A plurality of protrusions 121 are provided on the surface of the blade 106 that is inscribed in the upper fan plate 101 and the lower fan plate 102. Further, the upper fan plate 101 and the lower fan plate 102 are provided with a fitting hole 103 for fitting with the protrusion 121.

  As shown in FIGS. 5 and 6, the fitting hole 103 is formed with a stepped portion 122 formed substantially parallel to the outer surface of the upper fan plate 101 on the outer surface side of the fitting hole 103. The step portion 122 is formed such that the depth h of the step portion 122 is 2/3 or less of the plate thickness t of the upper fan plate 101.

JP-A-8-177789

  However, the conventional centrifugal fan of the electric blower still has room for improvement from the viewpoint of improving the reliability of the centrifugal fan.

  That is, in the above-mentioned conventional centrifugal fan (impeller), the thickness of the stepped portion is thinner than the plate pressure of the fan plate (front shroud and rear shroud), so the strength of the stepped portion is greater than the strength of the fan plate. It becomes weak. For this reason, when the centrifugal fan is rotated at a high speed, the stepped portion is damaged, the blade is not fitted to the upper fan plate and the lower fan plate, and the centrifugal fan may be disassembled.

  The present invention has been made in view of the above-described problems of the prior art, and even when the impeller is rotated at a high speed, the stepped portion is not damaged, and the electric blower having high reliability is provided. It aims at providing the used vacuum cleaner.

In order to solve the above-described problems of the prior art, the present invention provides a front shroud having an air inlet, a rear shroud spaced apart from the front shroud, and a plurality of sheets sandwiched between the front shroud and the rear shroud. The blade includes an impeller that generates suction air, and an electric motor that rotationally drives the impeller, and a plurality of protrusions are provided on a portion that contacts the front shroud and the rear shroud of the blade. The front shroud and the rear shroud are provided with a fitting port that fits with the protrusion, and the fitting port has an opening area on the outer surface side larger than an opening area on the inner surface side where the blade of the fitting port contacts. A step portion provided substantially parallel to the outer surface of the front shroud and the rear shroud is provided on the outer surface side of the fitting port. The thickness of the parts are to provide an electric blower which is formed substantially the same as the thickness of the front shroud and rear face shroud.

  As described above, the electric blower of the present invention is formed with the thickness of the stepped portion being substantially the same as the thickness of the front shroud and the rear shroud, so even if the impeller is rotated at a high speed, the stepped portion is A highly reliable electric blower can be provided without being damaged.

  According to the electric blower of the present invention and the vacuum cleaner using the electric blower, the stepped portion is not damaged even when the impeller is rotated at a high speed, and the electric blower with high reliability is used. Could have provided a vacuum cleaner.

The expanded sectional view in Embodiment 1 of the electric blower of the present invention The expanded sectional view which shows the crimping part of the impeller in Embodiment 1 of the electric blower of this invention The perspective view of the vacuum cleaner which incorporated the electric blower of this invention Sectional drawing which shows the impeller of the conventional electric blower Enlarged cross-sectional view showing a conventional electric blower before caulking of an impeller The expanded sectional view which shows the fitting hole of the impeller of the conventional electric blower

  According to a first aspect of the present invention, there is provided a front shroud having an air inlet, a rear shroud disposed at a distance from the front shroud, and a plurality of blades sandwiched between the front shroud and the rear shroud, And a motor that rotationally drives the impeller, and a plurality of protrusions are provided in a portion that contacts the front shroud and the rear shroud of the blade, and the front shroud and the rear shroud are provided with protrusions. The fitting port is formed so that the opening area on the outer surface side is larger than the opening area on the inner surface side with which the blade of the fitting port contacts. On the outer surface side, a stepped portion provided substantially parallel to the outer surface of the front shroud and the rear shroud is provided, and the thickness of the stepped portion is determined by the front shroud and the rear shroud. It is obtained by a loud thickness and electric blower which is formed substantially the same.

  As a result, the thickness of the stepped portion is substantially the same as the thickness of the front shroud and the rear shroud. Therefore, even when the impeller is rotated at a high speed, the stepped portion is not damaged and is reliable. A high electric blower can be provided.

  In the second invention, in particular, in the first invention, when the projection is crimped, an adhesive is applied to a space portion formed between the crimped projection and the stepped portion. is there.

As a result, it is possible to eliminate irregularities on the front and rear shroud surfaces on the outer surfaces of the front and rear shrouds, so that the air resistance is increased by the crimped protrusions and the turbulent flow in the crimped protrusions. Generation | occurrence | production can fully be prevented, and a highly efficient electric blower can be provided.

  In the third aspect of the invention, in particular, in the first aspect of the invention, when the projection is crimped, a coating is applied to a space portion formed between the crimped projection and the stepped portion. .

  As a result, it is possible to eliminate irregularities on the front and rear shroud surfaces on the outer surfaces of the front and rear shrouds, so that the air resistance is increased by the crimped protrusions and the turbulent flow in the crimped protrusions. Generation | occurrence | production can fully be prevented, and a highly efficient electric blower can be provided.

  In the fourth invention, particularly in the first to third inventions, nine or more blades are provided, and the impeller is rotationally driven by an electric motor at 30000 r / min or more.

  Thus, by providing nine or more blades, the frequency of the high-frequency sound of the airflow generated from the impeller can be kept away from the frequency band that is easy for the user to hear, and the high-frequency sound is sufficient to give the user discomfort. Can be prevented. Further, by sufficiently driving the impeller at 30000 r / min or more, the blowing efficiency of the electric blower can be sufficiently ensured.

  According to a fifth aspect of the present invention, there is provided a dust collection chamber for collecting dust, a hose communicating with the dust collection chamber, an extension pipe, and a suction tool, and the electric blower according to any one of claims 1 to 4 A vacuum cleaner having

  Thereby, a highly reliable vacuum cleaner with a high suction force can be provided.

  Hereinafter, preferred embodiments of the electric blower of the present invention will be described in detail with reference to the drawings. In the following description, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted.

(Embodiment 1)
Embodiment 1 of the present invention will be described with reference to FIGS.

  FIG. 1 is an enlarged cross-sectional view of Embodiment 1 of the electric blower of the present invention. FIG. 2 is an enlarged sectional view showing a caulked portion of the impeller in the first embodiment of the electric blower of the present invention.

  As shown in FIG. 1, the electric blower 1 is mainly mounted on the electric motor 2, the impeller 4 that is attached to the rotating shaft 3 of the electric motor 2, generates suction air, and is opposed to the outer periphery of the impeller 4. An air guide 7 in which a volute chamber 6 is formed by a plurality of guide vanes 5, an impeller 4, and an air guide 7 are enclosed, and airtightly attached to an anti-load side bracket 10 provided on the outer periphery of the electric motor 2. And a fan case 8 having an intake port 9 at the same time. Further, the non-load side bracket 10 constituting the electric motor 2 is provided with an exhaust port (not shown) for exhausting the air sucked by the impeller 4.

  The impeller 4 includes a front shroud 12a, a rear shroud 12b disposed at a distance from the front shroud 12a, and a plurality of blades 13 sandwiched between the front shroud 12a and the rear shroud 12b.

A plurality of protrusions 14 are provided on the portion of the blade 13 that contacts the front shroud 12a and the rear shroud 12b. Further, the front shroud 12a and the rear shroud 1
2b is provided with a plurality of fitting ports 15 that fit into the protrusions 14.

  As shown in FIG. 2, the fitting port 15 is formed such that the opening area on the outer surface P2 side is larger than the opening area on the inner surface P1 side with which the blade 13 of the fitting port 15 contacts. Further, on the outer surface P2 side of the fitting port 15, there is provided a step portion 16 provided substantially parallel to the outer surface P2 of the front shroud 12a. The thickness T2 of the step portion 16 is formed to be substantially the same as the thickness T1 of the front shroud 12a. Further, the step portion 16 is configured such that the upper end surface portion of the projection portion 14 does not protrude from the outer surface P2 of the front shroud 12a when the projection portion 14 is crimped. Further, the stepped portion 16 is formed such that the outer surface P3 of the stepped portion 16 is positioned on the blade 13 side by the thickness T3 of the crimped portion 14a of the projection 14 after the outer surface P2 of the front shroud 12a is crimped. Has been.

  Here, the thickness T1 of the front shroud 12a is normally 0.6 to 0.8 mm, and the thickness T3 of the crimped portion 14a of the projection 14 after being crimped is about 0.05 mm or less. It is set to become.

  The operation in the above configuration will be described. When power is supplied to the electric motor 2, the impeller 4 is rotationally driven by the electric motor 2 at a high speed of, for example, 30000 r / min or more, air is sucked, and suction air is generated. This suction air is guided from the intake port 9 to the inside of the impeller 4, then passes through the inside of the impeller 4 and is discharged from the outer periphery of the impeller 4. The suction air discharged from the outer periphery of the impeller 4 is rectified by passing through the inside of the volute chamber 6 formed by the adjacent guide vanes 5 of the air guide 7. The suction air rectified by the air guide 7 is guided into the anti-load side bracket 10, cools the electric motor 2, and then is discharged from an exhaust port (not shown) of the anti-load side bracket 10.

  At this time, even if the impeller 4 is rotationally driven at a high speed of 30000 r / min or more, the crimped protrusion 14 does not protrude from the outer surface of the front shroud 12a, and the surface of the front shroud 12a becomes smooth. Therefore, it is possible to sufficiently prevent air resistance and turbulence generated by the protruding protrusion 14 when the crimped protrusion 14 protrudes from the outer surface P2 of the front shroud 12a. Energy loss can be sufficiently reduced, and the blowing efficiency of the electric blower can be improved.

  Further, since the thickness T2 of the step portion 16 is formed substantially the same as the thickness T1 of the front shroud 12a, the step portion 16 is not damaged even when the impeller 4 is rotated at a high speed. A highly reliable electric blower can be provided.

  Furthermore, the surface of the front shroud 12a can be further smoothed by applying an adhesive or a paint to the space 17 formed between the crimped projection 14 and the stepped portion 16, and further the projection The fluid energy loss at 14 can be sufficiently reduced, and the blowing efficiency of the electric blower can be improved.

  In general, it is known that the frequency of the high-frequency sound generated by the impeller 4 is the product of Z and N, where Z is the number of blades 13 and N is the number of revolutions per second of the impeller. It is usually called NZ sound. A high frequency sound was generated at an integral multiple of the frequency of the NZ sound, and it was an unpleasant and unpleasant sound.

As a general technical means for reducing this high frequency sound, by increasing the number of blades 13, the frequency of the high frequency sound is kept away from the frequency band that can be easily heard by the user, thereby reducing unpleasant and unpleasant sound. Is considered. However, conventionally, the crimped protrusions 14 protrude from the outer surface of the front shroud 12a, and when the number of blades 13 is increased, the number of protrusions 14 protruding from the outer surface of the front shroud 12a becomes very large. The fluid energy loss is remarkably increased, and the suction performance of the electric blower is lowered, which is difficult to realize.

  However, in the configuration of the present embodiment, since the crimped protrusion 14 does not protrude from the outer surface of the front shroud 12a, high-frequency sound can be reduced while improving the suction performance.

  For example, when the number of blades Z is 6 and the rotation speed N is 36000 r / min (600 Hz), the frequency of the generated high frequency sound is 6 × 600 = 3600 Hz, which is a frequency band that is relatively easy for the user to hear and is unpleasant. It was a nice sound.

  Therefore, when the number of blades Z is 9 or more, since the rotation speed N is 36000 r / min (600 Hz), the frequency of the generated high-frequency sound is 9 × 600 = 5400 Hz, which is away from the frequency band that is relatively easy for the user to hear. It is possible to reduce unpleasant and unpleasant sounds.

  As described above, according to the electric blower of the present embodiment, since the thickness T2 of the stepped portion 16 is formed to be substantially the same as the thickness T1 of the front shroud 12a, the impeller 4 is rotated at a high speed. Even if it exists, the level | step-difference part 16 is not damaged and a reliable electric blower can be provided. Moreover, since the protrusion 14 after crimping does not protrude from the outer surface of the front shroud 12a, fluid energy loss at the protrusion 14 can be sufficiently reduced, and the blowing efficiency of the electric blower can be improved. it can. In particular, this effect becomes significant when the number of blades 13 increases or when the rotational speed of the impeller 4 increases.

  In the present embodiment, the configuration in which the step portion 16 is provided in the fitting port 15 of the front shroud 12a has been described, but the fitting port of the rear shroud 12b has the same configuration.

(Embodiment 2)
Hereinafter, Embodiment 2 of the present invention will be described with reference to FIG. Note that a description of the same components as those in the first embodiment described above is omitted.

  FIG. 3 is a perspective view of a vacuum cleaner incorporating the electric blower of the present invention.

  As shown in FIG. 3, the electric vacuum cleaner 30 mainly includes a vacuum cleaner main body 19 incorporating the electric blower 1 of the present invention, a hose 20 having one end detachably connected to the vacuum cleaner main body 19, and a surface to be cleaned. The suction tool 22 is configured to suck the dust, and the extension pipe 21 is connected to the hose 20 at one end and connected to the suction tool 22 at the other end.

  In the above configuration, the dust on the surface to be cleaned is sucked from the suction tool 22 by the suction air generated by the electric blower 1 of the present invention. Dust sucked from the suction tool 22 is collected by a filter (not shown) built in a dust collecting chamber (not shown) in the cleaner body 19 via the extension pipe 21 and the hose 20. At this time, the electric blower 1 of the present invention is a high-reliability, high-efficiency, low-frequency sound, high reliability, high suction performance, and low noise operating noise. realizable.

The electric blower of the present invention and the electric vacuum cleaner using the electric blower have a highly reliable electric blower and a vacuum cleaner using the electric fan without the step portion being damaged even when the impeller is rotated at a high speed. Therefore, the present invention can be suitably applied to fields / uses of household electrical appliances and industrial equipment using an electric blower.

DESCRIPTION OF SYMBOLS 1 Electric blower 2 Electric motor 3 Rotating shaft 4 Impeller 5 Guide blade 6 Volute chamber 7 Air guide 8 Fan case 9 Air inlet 10 Anti-load side bracket 12a Front shroud 12b Rear surface shroud 13 Blade 14 Protrusion 14a Clamping portion 15 Mating port 16 Step Part 17 Space part 19 Vacuum cleaner body 20 Hose 21 Extension pipe 22 Suction tool 30 Vacuum cleaner

Claims (5)

A front shroud having an air inlet; a rear shroud spaced apart from the front shroud; and a plurality of blades sandwiched between the front shroud and the rear shroud to generate suction air. Impeller,
An electric motor for rotationally driving the impeller;
With
A portion of the blade that contacts the front shroud and the rear shroud is provided with a plurality of protrusions,
The front shroud and the rear shroud are provided with fitting ports that fit with the protrusions,
The fitting port is formed so that the opening area on the outer surface side is larger than the opening area on the inner surface side with which the blade of the fitting port contacts.
On the outer surface side of the fitting port, a step portion provided substantially parallel to the outer surface of the front shroud and the rear shroud is provided,
The thickness of the said level | step-difference part is an electric blower currently formed substantially the same as the thickness of the said front surface shroud and the said rear surface shroud.   The electric blower according to claim 1, wherein an adhesive is applied to a space portion formed between the crimped projection and the step when the projection is crimped.   The electric blower according to claim 1, wherein a paint is applied to a space formed between the crimped protrusion and the step when the protrusion is crimped. 9 or more blades are provided,
The electric blower according to any one of claims 1 to 3, wherein the impeller is rotationally driven by the electric motor at 30000 r / min or more.   An electric vacuum cleaner comprising: a dust collection chamber that collects dust; a hose that communicates with the dust collection chamber; an extension pipe; and a suction tool; and the electric blower according to claim 1. Machine.